All Countries
Long Grove, IL
Full City Profile · Illinois · McHenry County County
4.4
/5.0
A
Great
8,266
Population
667/sq mi density
$235,368
Median Income
$101,162 per capita
$746,700
Home Value
$899,262 Zillow
$3,501
Median Rent
27.7% income on rent
48°F
Avg Temperature
260 sunny days/yr
A
Overall
4.4 / 5.0
Strong
A+
Economy
5.0 / 5.0
$235,368 median income, 2.1% unemployment
A+
Affordability
4.9 / 5.0
$746,700 home value, $3,501/mo rent
C+
Safety
2.5 / 5.0
0 violent crimes/100K
A+
Education
5.0 / 5.0
73.8% bachelor's degree or higher
Long Grove experiences four distinct seasons with an average annual temperature of 48°F (9°C). Winters average 21°F in January while summers reach 72°F in July. The area gets 260 sunny days per year. Annual precipitation totals 38.5 inches. The area receives 43.1 inches of snow annually. Air quality is rated Good with a median AQI of 43.
Temperature
21°F Jan (-6°C)
72°F Jul (22°C)
| Annual Average | 47.9°F |
| 11% below US avg | |
| January Average | 21°F (-6°C) |
| July Average | 72°F (22°C) |
| Sunny Days | 260 days/yr |
Geography
| Elevation | 761 ft (232 m) |
| Area | 4.9 sq mi (12.7 km²) |
| Population Density | 667/sq mi |
| Coordinates | 42.1950°N, 88.0110°W |
| Timezone | America/Chicago |
| County | McHenry County County |
| Nearest Airport | Chicago O'Hare International (ORD) 16 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 43.0 |
| Rating | Good |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0484 ppm |
| PM2.5 (Fine Particles) | 9.1 μg/m³ |
Natural Hazard Risk
| Overall Risk | Relatively Moderate |
| Risk Score | 90.8 / 100 |
| Social Vulnerability | 10.6 / 100 |
| Community Resilience | 84.0 / 100 |
Hazard Breakdown
| Tornado | Relatively High |
| Hurricane | Very Low |
| Earthquake | Relatively Low |
| Wildfire | Very Low |
| Flood | Relatively Moderate |
| Hail | Relatively Moderate |
| Strong Wind | Relatively High |
| Heat Wave | Relatively Low |
| Winter Weather | Relatively Moderate |
| Lightning | Relatively Moderate |
| Ice Storm | Relatively Low |
| Drought | Relatively Low |
| Cold Wave | Relatively High |
| Landslide | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Tsunami History
1 tsunami recorded within 500 km. Highest wave on record: 3.0 m (10 ft).
| Year | Location | Cause | Max Wave | Deaths | Distance |
| 1954 | MICHIGAN CITY, IN (LAKE MICHIGAN) | Avalanche | 3.0 m | 7 | 108 km |
Source: NOAA/NCEI Historical Tsunami Database. Sorted by wave height.
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 21°F (-6°C) | 1.6 in | Coldest |
| February | 25°F (-4°C) | 1.3 in | Driest |
| March | 36°F (2°C) | 2.5 in | |
| April | 47°F (8°C) | 3.6 in | |
| May | 58°F (14°C) | 3.4 in | |
| June | 67°F (20°C) | 3.9 in | |
| July | 72°F (22°C) | 3.9 in | Warmest |
| August | 70°F (21°C) | 4.1 in | Wettest |
| September | 63°F (17°C) | 3.8 in | |
| October | 51°F (11°C) | 2.4 in | |
| November | 38°F (4°C) | 2.7 in | |
| December | 26°F (-3°C) | 2.2 in |
Long Grove has a seasonal temperature swing of 51°F / from 21°F in January to 72°F in July. Total annual precipitation is 35.4 inches, with August being the wettest month (4.1") and February the driest (1.3").